Cardiovascular Overview/Output and distribution Flashcards
Where is the arterioles our system is maximum resistance?
Arterioles
Where does the blood change from being pulsatilla to steady flow?
Arterioles
How does a patient with Graves’ disease manifest symptoms in the fingernail beds?
- Hyperthyroidism —> INC basal metabolic rate —> Arteriolar vasodilation
- Diminished damping results in pulsatilla flow in capillaries which is observed in fingernail beds of patients
What are locations of pacemakers?
Normal - SA node
Others: AV Node, Purkinje fibers
What causes bradycardia in a patient with an injured AV Node?
- If AV node is injured, the ability to conduct is affected
- Purkinje fibers take over and have a slower intrinsic beat
How do conductions differ between prukinje vs AV node?
Fastest conduction is in the Purkinje fibers, awhile the AV has the slowest
How is Cardiac output calculated?
HR X SV
How is stroke volume calculated?
SV = EDV - ESV
How is ejection fraction calculated?
EF = SV/EDV
How do denervated baroreceptors affect heart response?
Cardiac output and HR responses are small compared to those with normally innervated baroreceptors
How does total cardiac denervation affect output?
During Exercise, increases in cardiac output are as much as normal individuals
What is the Fick Principle?
- Amount O2 delivered to capillaries plus amount O2 which enters capillaries from organ must equal amount O 2
carried away veins. - estimates organ oxygen consumption of organs
- consumption equals blood flow multiplied by the AV O2 difference
In Ficks principle, what are the constants?
Q1 - Rate of O2 delivery
Q2 - Net rate of O2 uptake
Q3 - Rate at which Venular O2 is carried away
How is the blood divided through the circulatory system?
64% - veins
14% - Arterial system
6% - Capillaries
How is left ventricular work calculated?
Product of stroke volume and mean aortic pressure.
